A. EF. Verrili— Mollusca of the New England Coast. 259 
form cannot be regarded as specifically distinct from the recent 
‘shells. The latter show much greater differences among themselves 
than those that distinguish the fossil from the ordinary form, known 
as V. borealis, while all the variations are connected together by 
intermediate forms. 
I also consider V. Novangliw Morse, a mere variation of this com- 
mon and variable species, hardly to be distinguished as a variety. 
It differs mainly in its thinner texture, lighter hinge-plate, and more 
transverse form—characters that are due partly to immaturity and 
partly to unfavorable conditions of growth. 
Living shells, of the typical form of V. borealis, have been dredged 
by the U. S. Fish Commission, off the eastern coast of Virginia, 
where it is not uncommon, at moderate depths (57 to 150 fathoms). 
Loripes lens Verrill. 
These Transactions, vol. v, p. 569, 1882. 
Jeffreys, in Proc. Zool. Soc. London, for 1882, p. 685, identifies 
our species with the Zoripes lacteus of Europe. I am unable to 
accept this identification. Although allied forms, they seem to me 
as distinct as other species of this group. 
Leda acuta (Conrad). 
Nucula acuta Conrad, Amer. Mar. Conch., pl. 6, fig. 3. 
Leda unca Verrill, Proc. U.S. Nat. Mus., iii, p. 401, 1880; these Transactions, v, 
p. 572, pl. 58, fig. 41, 1882 (? non Gould). 
Leda acuta Tryon, Amer. Mar. Conch., p. 182, pl. 38, fig. 496 (poor). 
? Leda commutata Philippi. 
PLATE XXX, FIGURE 15. 
Although this species was referred by me to Leda wnea Gould, 
later investigations have rendered this identification doubtful. It is, 
however, as indicated in my former papers, probably identical with 
LL. acuta Conrad, which was described much earlier. By Jeffreys it 
has been referred to ZL. fragilis (Chemn., sp.), which he considers 
identical with Z. commutata Philippi. The identification of Chem- 
nitz’s figure is doubtful, and moreover he was not a binomial writer ; 
it is therefore useless to attempt to restore his name. Not having 
seen authentic specimens of ZL. commutata (L. fragilis Jeffreys) 
from Europe, Iam unable to express any decided opinion as to its 
identity with our shell. In any case, acuta seems to be the oldest 
available name for our shell. 
In this shell the posterior dorsal area, when seen from the dorsal 
Trans. Conn. ACAD., Vou. VI. 33 JULY, 1884, 
